Ball mill



Jan. 23, 19 M. s. MISCHANSKI BALL MILL 3 Sheets-Sheet 1 Filed Nov. 12,1959 15 ill.

JNVENTOR.

fhPO/V a. N/JfHANf/r/ Jan. 23, 1962 M. s. MISCHANSKI BALL MILL 3Sheets-Sheet 2 Filed Nov. 12, 1959 III Jan. 23, 1962 Filed Nov. 12. 19593 Sheets-Sheet 3 ATTORNEY.

3,018,0fil Patented Jan. 23, 1962 *Llited flee are secured by bolts 20or equivalent fastening means to $018,061 the outer ends of thetruncated sections respectively. BALL MEL The to sectio 7 11 ludes a hoer sha ed u er end Myron S. Mischanslri, 27 Englewood Road, Clifton, NJ.9 p I} 1 C P p pp Figed NW. 12 19599 gag. N0. 352,343 M1 through whichthe sol d material to be ground is fed 4 (312mm m a to the mill. The topsection 17 opens into the truncated section 15 with the peripheral innerface 22 formed as a continuation of the upper portion of the annularface solid material. 1?,- of the medial section 12. Similarly the lowertrun- The invention comprehends a ball mill in which magcated section 16has its inner peripheral face 23 formed netically attractable balls rollagainst an inner annular as a continuation of the lower portion of theinner anface portion of the mill by the magnetic attraction of nularface 13. The lower tubular section 18 provides an electromagnets mountedfor rotation about the periphery outlet for discharging the groundmaterial from the mill. of the mill in a plane extending through saidinner face In order to direct the material to be crushed and portion.pulverized toward the inner face 13 of the medial sec- Ball mills havebeen provided for grinding solid matction 12 and between the same andthe rotating balls 14, rial in batches or a small quantity thereof at atime, a conical shaped bafile 24 is provided which is supported which isdeposited in the mill with metal balls and when within the upper section15 by a plurality of radially arthe grinding is completed, the groundmaterial is separanged circumferentially spaced straps 25 affixedthereto rated from the balls and removed from the mill. This at theirinner ends and secured at their outer ends in type of ball mill requiressome means for separating the 20 radially arranged slots in the upperface of the medial ground material from the balls before another batchor section 12. The baflle 24 slopes toward the inner face quantity canbe inserted in the mill. In order to provide 13 of the medial section 12and has its lower peripheral a continuously operated ball mill in whichthe ground edge annularly spaced from the inner face 22 of the materialis removed from the mill as the same is ground, truncated section 15 topermit of the continuous gravitathe present invention includes means forcontinuously 25 tional feeding of the solid material. The solid materialfeeding the material to be ground toward the peripheral may be granularin foim or partly divided and of a size area of engagement of themagnetically attractable balls to pass freely between the bafile 24 andthe truncated with the inner face portion of the mill and forcontinusection 15. ously discharging the crushed and pulverized materialin Below the baflle 24 is a conical shaped deflector or a direction awayfrom the area of engagement of the shield 26 which is located axiallywithin the medial secballs with said face portion of the mill. tion 12and extends upwardly between the balls and is A further object of theinvention is to provide means removably supported by a plurality ofradially arranged for supporting the balls so as to retain the same iadcircumferentially spaced straps 27 secured thereto at jacent relationto the inner face of the mill and substantheir inner ends and secured atthe outer ends in radially i ll i h plang f th electromagnets h h illarranged slots in the lower face of the medial section is not in use sothat the balls will be attracted by the Th hi d 26 functions to directthe crushed and electromagnets when the same are energized, pulverizedmaterial dropping from the balls during rota- Still another object ofthe invention is to provide a ball n d wn the Coni al fa e thereof. Theshield also funcmill of said character which is so constructed and ar-U035 10 pp the balls W n t mill iS not in use so ranged th t th parts thf may b readily remcved as to retain the same substantially in ahorizontal plane for cleaning the interior of the mill. extendingmedially through the medial section.

With the foregoing and other objects in view, refer- The balls 14 rotatein an annular P about the ence is now made to the followingspecification and 30- side face of the medial section 12 Of the casingby means companying drawings in which the preferred embodiof themagnetic attraction of a plurality of electromagnets ments th of are illtrat d, 29 which are mounted for rotation about the medial In thedrawings: section 12 with the axis of each of the cores 30 thereof FIG.1 is a vertical sectional view through a ball mill being radiallydisposed in a I ta p ane xt nding constructed in accordance with theinvention. medially through the medial Section- The electromag- FIG. 2is a horizontal sectional view taken approxinets 29 correspond in numberto the number of the balls mately on line 2-2 of FIG. 1 on a reducedscale. and are equally spaced circumferentially about the medial FIG. 3is a top plan view of the mill. section. Each of the electromagnets 29produces an elec- FIG. 4 is a vertical sectional view of a modified formtric field which extends through the medial section 12 of ball millconstructed in accordance with the invenand attracts one of the balls.The medial section 12 is tion. of any desired hard non-magnetic materialwhich is per- Referring to the drawings, the ball mill includes a meableto a magnetic field such as ceramic materials, hard casing 10 having abase 11 adapted to be affixed to a supmetal alloys such as bronzes andmanganese alloys and port for supporting the casing in upright relation.The the like, and other hard materials and metals not apprecasingincludes a medial section 12 of annular formaciably affected by amagnetic field. The balls 14 may be tion having an annular inner face 13preferably of consteel, nickel, tungsten carbide and the like or othermatecave formation in vertical section against which face a rials andmetals attracted 'by a magnetic field. Heavy plurality of magneticallyattractable balls 14 are adapted balls facilitate crushing andpulverizing of the material. to roll to effect crushing and pulverizingof the solid However, hard lighter balls may be employed. material fedtherebetween. The electromagnets 29 are mounted on a metal frame Thecasing also includes upper and lower truncated sec- 32 Which isrotatably supported on the base 11. The tions 15 and 16 and top andbottom cylindrical sections said frame includes a ring member 33 havingapertures 17 and 18. The said sections are in axial alignment 34 inwhich the cores 30 are secured with the inner ends with the medialsection 12 to provide a passageway for of the cores located in closelyspaced relation to the the material to be ground. The truncated sections15 outer periphery of the medial section 12. The frame 32 and 16 aresecured by bolts 19 or equivalent fastening also includes upper andlower frame sections 35 and 36 means to the upper and lower endsrespectively of the respectively which are secured to the ring member 33by medial section, while the cylindrical sections 17 and 18 bolts 37 orequivalent fastening means and with radial This invention relate to aball mill for comminuting material fed thereto.

bearings 38 and 39 arranged between the tubular sections 17 and 18 ofthe casing and the upper and lower ends of said frame sectionsrespectively. A thrust bearing 40 is arranged between the base 11 andthe lower end of the frame section 3 6. The frame sections 35 and 36 areprovided with a plurality of circumferentially spaced openings 41 and 42respectively for admitting air between the frame 32 and the casing 18 soas to prevent overheating of the electromagnets 29.

The frame 32 is rotated about the casing 16 by any desired means such asby an endless belt 44 engaging in an annular groove 45 provided in theframe section 36 and with the belt driven by any desired means (notshown). The electromagnets 29 are continuously energized and leadingfrom the ends of each of the coils are conductors 46 and 47 which areelectrically connected to conductor rings 48 and 49 affixed to the framesection 36 adjacent the bottom thereof. The conductor rings areinsulated from the frame section 36 by means of an insulating ring 50secured in fixed position between said frame section and the conductorrings. The conductor rings are connected with a source of current supplyby means of conductor brushes 51 and 52 adjustably carried by a holder53 which is of non-conductive material and is supported on the base by astud 54 to dispose the brushes with the inner ends thereof in engagementwith the conductor rings respectively. One of the brushes is adapted tobe connected with the positive side of an electric power source by aconductor 55 while the other is adapted to be connected with thenegative side thereof by a conductor 56.

A double pole switch 57 is interposed in circuit with said conductorsfor making and breaking the circuit with the electromagnets. Energizingthe electromagnets produces magnetic fields which attract the balls 14causing the same to rotate with the electromagnets about the medialsection 12 of the casing and against the annular face 13 thereof so asto crush and pulverize the solid The electromagnets and balls may be ofany desired number and in the present embodiment five electromagnets andfive balls are provided.

The material to be crushed and pulverized may be fed to the mill eitherby gravity or air pressure. In employing air pressure for this purposethe material may pass through the mill either downwardly or upwardly,and as illustrated in FIG. 4 of the drawings, a bafile is provided fordirecting the material upwardly toward the inner face of the medialsection and the rotating balls.

With the exception of the formation and arrangement of the baflie, themill in this form of the invention is similar to the previous form andincludes a casing 60 having a base 61 adapted to be affixed to asupport. The casing also includes a medial section 62. of annularformation having an annular face 63 against which a plurality ofmagnetically attractable balls 64 are adapted to roll. The casing alsoincludes upper and lower truncated sections 65 and 66 and top and bottomcylindrical sections 67 and 68. The upper and lower truncated sections65 and 66 are similar to the sections and 16 in the previous form of theinvention while the top section 67 is the same as the top section 17 inthe previous form with the exception that the hopper is eliminated. Thebottom section 68 is similar to the section 18 with the exception thatthe same projects below the base for connection with a conduit forfeeding material by air pressure. The said sections are similarlysecured together by bolts 69 or equivalent fastening means and aplurality of electromagnets 70 corresponding in number to the number ofballs 64 are provided. The electromagnets 70 are similar to theelectromagnets 29 in the previous form of the invention and are mountedon a metal frame 72 similar to the metal frame 32, the metal frame 72being rotatably supported on the base 61. The electromagnets 70 arecontinuously energized during operation of the mill and leading from theends of the coils of the electromagnets are conduits 76 and 77 which areconnected to conductor rings 78 and 79- mounted in fixed position on thelower portion of the frame 72 as in the previous form of the invention.The rings are insulated from the frame 72 by an insulating ring 88 andare engaged by conductor brushes 81 and 82 adjustably carried by aholder 83 of non-conductive material which is supported on the base 61by a stud 84.

In this form of the invention a hollow baffie 86 is provided havingconical shaped upper and lower wall portions 87 and 88 and a concavemedial wall portion 90 extending peripherally thereabout and which formsa support for the balls 64 when the mill is not in operation. The baflle86 is secured in position by a plurality of radially arranged upper andlower straps 90 and 91 affixed thereto at their inner ends and withtheir outer ends secured in radially arranged slots in the upper andlower faces of the medial section 62. The lower wall portion 88 of theinatfie functions to direct the material to be crushed and pulverizedbetween the balls 64 and the inner face 63 of the medial section 62while the upper wall portion 87 reduces the area of the flow within theupper section 65 so as to avoid reduction in air pressure.

A double pole switch 93 is interposed in circuit with the conductorrings 73 and 7? for connecting the electromagnets with a source ofcurrent supply. Energizing the electromagnets produces magnetic fieldswhich extend through the medial section 62 and attract the balls causingthe same to rotate with the electromagnets respectively about the medialsection 62 and against the annular face 63 thereof.

The medial section 62 like the medial section 12 may be of any desiredhard non-magnetic material which is permeable to a magnetic field suchas ceramic materials, hard metal alloys such as bronzes and manganesealloys and the like, and other hard materials and metals not appreciablyaifected by a magnetic field. The balls 64 may be steel, nickel,tungsten carbide and the like or other materials and metals attracted bya magnetic field.

The frame '72 is rotated about the casing 68 by any desired means suchas by an endless belt 94 engaging in an annular groove 95 provided inthe frame 72 with the belt driven by any desired means (not shown).

in this form of the invention the material to be ground which may be ingranular or partly broken condition is fed upwardly by fluid pressurethrough the bottom section 68. Any desired means may be provided forfeeding the material to the bottom section. The lower wall portion 88 ofthe battle directs the material radially toward the annular face 63 ofthe medial section and the balls 64 rotating against the annular face 63by the magnetic attraction of the electromagnets 7t) rotating about theperiphery of the medial section functions to crush and pulverize thematerial. The crushed and pulverized material is carried along with thefluid pressure and discharged through the truncated section 65. Anydesired means may be employed for conducting the crushed and pulverizedmaterial from the truncated section 65.

While the preferred forms of the invention are shown and describedherein, the same is not so limited but shall cover and include any andall modifications thereof which fall within the purview of theinvention.

What is claimed is:

1. In a ball mill for comminuting solid material, a casing arranged on avertical axis and having an opening for feeding the material to becomminuted and another opening for discharging the comminuted materialtherefrom, said casing having an annular inner face intermediate saidopenings against which the solid material is comminuted, a plurality ofmagnetically attractable balls arranged within said casing for rollingengagement against said annular face for comminuting the solid material,means carried by said casing supporting said balls in adjacent relationto said annular face when the balls are at rest, means carried by saidcasing for directing the material to be comminuted toward said annularface,

a plurality of electromagnets corresponding in number to the number ofsaid balls arranged with their cores disposed radially about saidannular portion of said casing, a driven rotatable frame on which saidelectromagnets are mounted, means rotatably supporting said frame onsaid casing, and conductor means carried by said frame and connectedwith said electromagnets, and means carried by said casing engaging saidconductor means for connecting said electromagnets with a source ofcurrent supply to energize said plurality of electromagnetssimultaneously and continuously during the rotation of the same frame tothereby establish magnetic fields passing continuously through saidballs respectively for causing said balls to rotate against said annularface with the rotation of said frame.

2. In a ball mill for comminuting solid material, a casing arranged on aVertical axis and having an opening for feeding the material to becomminuted and another opening for discharging the comminuted materialtherefrom, said casing having an annular inner face intermediate saidopenings against which the solid material is cornminuted, a plurality ofmagnetically attractable balls arranged within said casing for rollingengagement against said annular face for comminuting the solid material,means carried by said casing supporting said balls in adjacent relationto said annular face when the balls are at rest, means carried by saidcasing for directing the material to be comminuted toward said annularface, a plurality of electromagnets corresponding in number to thenumber of said balls arranged with their cores disposed radially aboutsaid annular portion of said casing, a driven rotatable frame on whichsaid electromagnets are mounted, means rotatably supporting said frameon said casing, and conductor means connected with said electromagnetsadapted to be connected to a source of current supply to energize saidplurality of electromagnets simultaneously and continuously during therotation of the same frame to thereby establish magnetic fields passingcontinuously through said balls respectively for causing said balls torotate against said annular face with the rotation of said frame.

3. In a ball mill for comminuting solid material, a casing arranged on avertical axis and having open upper and lower ends for feeding thematerial to be comminuted and for discharging the comminuted materialtherefrom, said casing having an intermediate annular portion providedwith an annular inner face against which the solid material iscomminuted, a plurality of mag: netically attractable balls arrangedwithin said casing for rolling engagement against said annular face forcomminuting the solid material, means carried by said casing supportingsaid balls in adjacent relation to said annular face when the balls areat rest, means carried by said casing for directing the material to becomminuted toward said annular face, a plurality of electromagnetscorresponding in number to the number of said balls arranged with theircores disposed radially about said annular portion of said casing, adriven rotatable frame on which said electromagnets are mounted, meansrotatably supporting said frame on said casing, conductor rings carriedby said frame, means electrically connecting said electromagnets withsaid rings, and contact means carried by said casing engaging said ringsfor connecting said electromagnets with a source of current supply toenergize said electromagnets to thereby establish magnetic fieldspassing through said balls respectively for causing said balls to rotateagainst said annular face with the rotation of said frame.

4. In a ball mill for comminuting solid material, a casing having anopening for feeding the material to be comminuted and another openingfor discharging the comminuted material therefrom, said casing having anannular wall portion provided with an annular inner face locatedintermediate said openings against which the solid material iscomminuted, a plurality of magnetically attractable balls arrangedwithin said casing for rolling engagement against said annular face forcomminuting the solid material, means carried by said casing fordirecting the material to be comminuted toward said annular face, aplurality of electromagnets arranged with the cores disposed radiallyabout said annular wall portion, a driven rotatable frame rotatablysupported on said casing and on which said electromagnets are mountedfor rotation therewith, said electromagnets when energized providingmagnetic fields passing through said annular wall portion and attractingsaid balls for causing said balls to rotate against said annular facewith the rotation of said frame, conductor rings carried by said frame,means electrically connecting said electromagnets with said rings, andcontact means carried by said casing engaging said rings for connectingsaid plurality of electromagnets simultaneously and continuously duringthe rotation of the same frame with a source of current supply toenergize said electromagnets to thereby establish magnetic fieldspassing continuously through said balls for causing said balls to rotateagainst said annular face with the rotation of said frame.

References Cited in the file of this patent UNITED STATES PATENTS529,766 Wheeler Nov. 27, 1894 1,546,330 Ullrich July 14, 1925 1,894,106Lehrack Jan. 10, 1933 FOREIGN PATENTS 24,392 Great Britain May 21, 1908

